Isolation and characterization of the female-specific protein (vitellogenin) in mature female hemolymph of the prawn Penaeus chinensis

Abstract

Purifying and characterizing the female-specific protein (vitellogenin) from the hemolymph of mature female prawns, Penaeus chinensis, were the objectives of this study. Hemolymph was stained with Sudan Black B and fractionated by an ultracentrifuge. A specific protein (vitellogenin) appeared in the third fraction of the female hemolymph, based on polyacrylamide gel electrophoresis (PAGE), Western blotting and immunoprecipitation. A purified vitellogenin was obtained from PAGE and electroelution. Two polypeptide subunits (191 and 85 kDa) were detected in SDS-PAGE. The purified vitellogenin was considered as a lipoglycophosphoprotein on the basis of staining data. Amino acid composition was also determined in the purified vitellogenin after acid hydrolysis. A very low level of cysteine was detected. Non-disulfide bonds were found in the binding of polypeptide subunits.